Not everyone has the comfort to work out and train in a tempered and cozy gym with constant temperature and humidity, wether it is for practical or financial reasons, or because the very discipline that is being trained requires a particular and sometimes extreme environment.
The influence of temperature on training and performances is as diverse as it is critical, and sometimes, even a few degrees can make a world of difference.
Temperature can influence physical performances on different levels : first, the ambient temperature is going to have an impact on the body and metabolism as a whole. Then, if exposure to extreme temperature is prolonged, and ends up cooling down or warming up particular tissues, a change in muscle temperature for instance, it can also have a big impact on performances. Also, living in a specific climate, even if one actually trains inside in a neutral, tempered environment, can have some influence on training and recovery.
The interesting thing is that when it comes to temperatures, both end of the spectrum (hot and cold) have most of the same effects on our physiology and metabolism (give or take a few exceptions) and those effects might be profitable or undesirable depending on what one is training for.
Let’s look at it from a sport specific standpoint.
A review of many different studies looking at the influence of temperature on performance showed that there is an ideal muscle temperature range to train at when it comes to endurance efforts : between 31°C (88°F) and 37°C (99°F). You will notice that these temperatures are actually lower than the average normal muscle temperature which is between 35°C (95°F) and 37°C (99°F). So training in a colder environment (cold enough to bring down one’s muscle temperature) or artificially cooling one’s body (cold bath) before an effort has been shown to increase endurance and total work capacity in a prolonged effort.
Here is how it works : One of the body’s response to extreme muscle and core temperature wether hot, or cold (above or below the temperatures mentioned earlier) is going to be an increase in catecholamines (adrenaline and noradrenaline) secretion. This hormonal response is going, in return to increase glycogen (form of glucose, stored in the muscles and the liver, one of the most efficient and potent source of energy) consumption. The end products of anaerobic glycolysis (process of breaking down glucose or glycogen without oxygen to produce ATP, see article about creatine) are lactic acid and pyruvate. The acute accumulation of lactate and pyruvate is what creates the burning feeling in the muscles during a prolonged period of effort. Therefore, an increase in glycogen use creates an increase in lactate and an increase in discomfort (or even pain) in the muscles, seriously reducing one’s endurance capacity. Also, fast diminishing glycogen stores can be a reason for reduced endurance in themselves. Indeed, glycogen is paramount when it comes to producing ATP even in a more aerobic performance, therefore, totally depleted glycogen stores would simply stop an athlete on the spot (also known as « hitting the wall »).
ADP (adenosine diphosphate, see article about creatine) replenishment has also been found to be much slower and less efficient above and below the temperature range mentioned earlier, this obviously also limits endurance.
It should be noted that when training in the heat, the main limiting factor for endurance isn’t actually lactate accumulation or even decreased ATP stores : When the body reaches a given core temperature (somewhere between 39°C/102°F and 40°C/104°F), the nervous system basically starts shutting down the body’s ability to recruit muscle fibers as a protective response to excessive body temperature. Also overall physical discomfort (feeling sick, overheated and nauseated) usually limits prolonged performances in the heat.
So training in a slightly colder environment, or cooling down the muscles/body before an effort is simply going to delay the increase in muscle and body temperature generated by physical activity, allowing the athlete to train that much longer without experiencing an increase in lactate accumulation or a decrease in ADP replenishment. Another benefit of training in a colder environment is an increased oxygen uptake, resulting in a better nutrient and oxygen delivery to the muscles, allowing for better performances.
When it comes to short, intense efforts, such as sprinting, jumping or weightlifting, everything changes.
Indeed, good performances in this kind of effort require maximum rate of force production (or power output) from a muscle. And it has been clearly established that the warmer (even several degrees above average) a muscle is, the better its force production is going to be. Its endurance will definitely not be optimal, but endurance is not the concern in that situation. So even if, when it comes to endurance, fine tuning is required (not too cold, not too hot) when it comes to powerful, intense, and short bouts of effort, the warmer, the better.
Since we now know that training in extreme temperatures affects our hormonal levels, we can deduce that it also affects our recovery, and several studies have indeed found that levels of catabolic hormones such as cortisol were higher after training in extremely cold or hot environments than after training in neutral (indoor) temperatures, resulting in higher protein breakdown.
A fascinating study following a group of US Marines for twenty-four days of field training in cold and wet weather showed a serious increase in oxidative stress (increase of the body’s toxicity resulting in cellular damages and sometimes malfunctions) even in subjects supplementing with antioxidants.
Another fact that can be of importance but that is often overlooked is that the climate in which one lives, (even if you train in a neutral environment) can affect one’s physiological levels before and after training and still have an impact on one’s performances. For instance, when living in the cold, we automatically use up more energy for thermoregulation, and it has been established that fifty percent of that energy comes from fat and thirty percent from glycogen (the last 20% are split between amino acids and glucose breakdown). So one’s energy stores could be altered independently of where and how one trains, even before performing any effort. As for living in the heat, our perspiration rate will be increased and we might face dehydration much faster even without the influence of strenuous physical activity.
Now that we have a better idea of how temperature can influence, for better or worse, our performances, there is a few advices, gathered from reliable and experienced sources that can be applied to keep one’s training on track even through the worst climatic conditions, some of it is common sense, but there are a few tricks worth discovering :
1. Dress accordingly : This one is pretty obvious and self explanatory, it is not advisable to run a half marathon by -1°C/30°F in a monokini ! But one might think that because the body generates heat during exercise, wearing enough layers of clothes in the cold is useless, and it might actually make sense with what was mentioned earlier about keeping the body coldER, and it might even be true to some point. But when it comes to seriously extreme conditions (close or below 0°C/30°F or over 35°C/95°F) it is better to take precautions, here’s why : The bigger the temperature difference between the skin/body and the air is, the more the body is going to have to use energy and water to thermoregulate, by dressing up warm enough or light enough one facilitates and supports the body’s thermoregulation process. Also when training in the cold, if dressed too light, one’s sweat might actually cool off too fast, which might result in catching a cold.
2. Hydrate : Again, nothing new here, except that there is hydrating and hydrating. Indeed, in specially cold environments it is a good idea to drink a warmer beverage (not lukewarm or tempered, WARM) since drinking something cool would make the body use more energy for thermoregulation. The same principle applies for hot weather, it is better to avoid icy cold beverages to avoid creating too big of a temperature difference with the body. Also drinking enough is as much a concern in cold weather as it is in hot weather. Indeed, even though one might sweat less in a cold environment, the thermoregulation process of maintaining our body temperature uses up a lot of water, so dehydration is always a concern even in the cold. The hydration guidelines by the National Academy of Sports Medicine (NASM) are as follow : The minimum average consumption of water for men is three liters per day (thirteen cups) and two liters for women (nine cups). Fourteen to twenty-two ounces (four to six dl) should be consumed two hours before exercise. Six to twelve ounces (one and a half to three and a half dl) should be ingested every fifteen to twenty minutes of exercise. Sixteen to twenty-four ounces (five to seven dl) of fluid should be ingested for every pound of bodyweight lost after training. Keep in mind these are recommendations, depending on the intensity and duration of the workout as well as one’s bodyweight, a higher quantity of fluid might be necessary.
3. Eat and supplement accordingly : During winter, or when training in a cold environment, the body’s metabolic rate will increase, that means burning more calories, mainly from fat, it sounds like a great thing, but it could seriously impair one’s energy stores (specially for someone with already healthy/low body fat), so eat plenty of rich (healthy) food. Supplementing can also be a good thing at both ends of the temperature spectrum, since we learned earlier that protein breakdown increases in extreme temperature (due to a more catabolic environment) supplementing with BCAA (Branched chain amino acids) or amino acids, as well as protein powder to ensure proper recovery might be an option. When it comes to cold, multi-vitamins and minerals supplements could help relieve some of the oxidative stress.
4. Sleep : This one is also not very new or original, but keep in mind that sleep is one of the best way to stimulate an anabolic environment in the body and support muscle recovery, specially if the climate you train in generates higher levels of catabolic hormones.
5. Warm-up/Cool-Down : Now this gets very specific and interesting. In warm/hot weather, the warm-up will still be necessary but might be much shorter than usual, if you are about to perform a low-impact, prolonged effort, it might actually be good too warm-up as little as possible to avoid increasing body and muscle temperature too much. I AM IN NO WAY ADVISING ANYONE NOT TO WARM-UP. A good warm-up is necessary for the nervous system and the body’s articulation to get ready for the effort and performance ahead, there is no short-cut. But even though it is ALWAYS NECESSARY to prepare for the effort, being too warm (literally) might not be ideal. However, the cool-down phase in a specially hot weather is more important than ever and should be as extensive as needed. When it comes to cold weather, a warm-up will obviously be longer and more thorough (although not too long either when it comes to endurance effort, I suppose you’re starting to get the idea), it might actually take longer than the performance itself, depending on the specifics of the sport (weightlifting for instance) and the situation at hand. A very good trick to get as ready as possible, as fast as possible for a short, intense effort in the cold is the use of muscle rub. This practice is fairly common in power and olympic lifting, but is applicable in many different disciplines. Applying muscle rub (tiger’s balm for instance) on the main muscles of the body right after the physical warm-up gets the muscles even more prepared and efficient for the performance to come. Some strength athletes even use it before competitions, regardless of the weather or temperature.
6. Adapt your workout/training sessions accordingly : Maybe I should have begun with that one, it is the most obvious, but probably the most neglected : to get the best out of a workout in extreme conditions, one can’t train as if one was training in a cozy, tempered gym/environment. It is crucial to keep the workouts as short and efficient as possible, focusing on the essential and dispatching the workload and objectives throughout the week/month to make sure one gets what is needed out of every session and still keeps on progressing without overtraining and impairing one’s recovery.
We all know now, that extreme climatic conditions are no excuse to avoid training and have all the tools needed to perform in any kind of weather !
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